Direct Reduction : Transition from Natural Gas to Hydrogen?

Abstract

The ambitious goals of the EU in the field of climate protection and reduction of CO2-emissions are a huge challenge for the European steel industry. Today, the standard route for production of high quality steel grades is the BF/BOF route, which is almost working at its physical optimum. Alternative production routes must be developed to transform steel production in a post-fossil and CO2-free industry as demanded by politics. Since reduction of iron ore has the highest energy demand in steel production, a CO2-free reduction agent is needed. A possible replacement could be hydrogen, if it is produced by electrolysis with renewable energies. Wind and solar energy will then become the new basis for steel production. This paper gives a concept of a hydrogen-based production of DRI. The hydrogen demand is calculated to be in the range of 600 Nm³ per ton of iron and the total electricity consumption will be about 3.31 MWh/tH2BI. If compared to classical production of DRI, the energy costs will increase by factor 5.5, which is a strong obstacle for a realization of such a process under current conditions. Nevertheless, the new process should be investigated in detail, in e.g. pilot plants, to be prepared when market conditions or regulations may change.